Abstract: The invention is directed to an apparatus for mitigating the load impact on a surface watercraft and passengers therein, during high speed travel. The hull includes a damping cavity for mitigating the load impact on the surface watercraft. The damping cavity is positioned on a dry portion of an undersurface of the hull between a forward end and an aft end of the hull. The damping cavity includes a porous plate on the undersurface, and a deck plate within the hull body. The deck plate and the porous plate are separated by a gap, and an inflatable bladder may be positioned in the gap between the plates.

Abstract: A high-speed water vessel including a steering arrangement for reducing cavitation and its effects. The arrangement includes a twisted rudder pair located downstream of a high-speed propulsor. The rudder pair may also be contoured at a bottom portion thereof. The propulsor has at least one propeller having a propeller diameter. In operation, the propulsor produces a slipstream that contracts with distance from the propeller. To avoid the effects of cavitation, the twisted rudder pair is positioned outside and adjacent to the slipstream diameter, with the rudders of the rudder pair separated by a distance that is less than the diameter of the propellers. The rudders of the rudder pair may be in a substantially parallel orientation with respect to each other. In gas turbine applications, the rudder pairs may be rotated towards each other to produce a rudder bucket for producing a negative thrust for stopping the high-speed water vessel.

Abstract: A hydrofoil stabilizer fixed to an underwater hull and provided with a pair of pivotally deflectable control flaps through which surface lift on the stabilizer is controlled, is provided with trailing edge tabs on both of the flaps that are pivotally deflected in the same direction to further offset and thereby improve recovery from surface jam inducing lift force on the stabilizer which adversely affects maneuvering control.

Abstract: The inventive apparatus exercises control of the water flow which is discharged from a marine waterjet propulsor. Typical inventive embodiments comprise plural horizontal and plural vertical blade-like structures which together describe an open-ended, box-like rectilinear configuration characterized by at least two adjacent channels. Every vertical blade-like structure includes, at its aft end, a “steering” flap which is pivotable about a vertical axis. Some inventive embodiments advance marine craft reversing by implementing one or more bucket-like devices behind the inventive apparatus.

Abstract: Cavitation of a hydrofoil element, such as the rudder of a marine vessel, om exposure to a body of water during onset flow at different angles to the chordal axis of the rudder profile, is suppressed by a tab on the lower end tip of the rudder. Such tab has external surfaces thereon which affect flow separation relative to the rudder so as to suppress or delay cavitation.

Abstract: The quantity of gases dissolved in liquids is determined by introducing a quid sample into a hollow cylinder with a plunger, retracting the plunger to create a void space into which gases originally dissolved in the liquid sample diffuse, compressing the gases into a reduced volume, measuring the absolute pressure of the gases, and calculating the amount of gases originally dissolved in the liquid from the absolute pressure, the temperature, the vapor pressure of the liquid at the prevailing temperature, the volumes of liquid and the final volume of the gas, by using the ideal gas law.

Abstract: A rubber bladder enclosed in a pressure tank having a valved opening is inflated by bladder inflation means to a pressure corresponding to the hydrostatic or other pressure of the environment to be sampled. Once the apparatus is located in the environment which is to be sampled, means for slowly exhausting the gas from the bladder, possibly a pump, are activated whereby hydrostatic or other pressure collapses the bladder and a fluid sample quiescently fills the pressure tank through the valved opening. When sample collection is complete, the valved opening, which is locally or remotely controllable, is closed and the sample is retrieved. Residual or ullage gas in the bladder maintains the sample at the pressure at which it was collected. Bladder inflating means are again employed after apparatus retrieval to initiate sample flow from the tank to an examining device or instrument at the same pressure that exists in the sampler.